Hydrogen Peroxide → 4-Bromoanisole

Temperatur

-78 °C

In a 500 mL round bottom flask was charged 2,4-dibromoanisole (5.0 g, 18.8 mmol) followed by 200 mL of dry tetrahydrofuran under nitrogen. The reaction mixture was then cooled to −78° C., and n-butyllithium (16.11 mL, 22.56 mmol) was added dropwise. The reaction mixture was stirred for 30 min at −78° C. The reaction mixture was then warmed to 0° C. and trimethylborate (2.57 mL, 22.56 mmol) was added dropwise. The reaction mixture was stirred at room temperature for 30 min. 5 mL of glacial acetic acid was added followed by 10 mL of 35% wt. hydrogen peroxide in a drop wise fashion. The reaction was allowed to stir 12 h at room temperature. The reaction was quenched with 1 N HCl, extracted with ethylacetate (100×3) and the combined organic phases were dried over Na2SO4, filtered and evaporated under reduced pressure. Purification by column chromatography yielded 1 g (26%) of 3-hydroxy, 4-methoxybromobenzene (white crystals). (96:4 Hexanes:ethylacetate).

1. temperatureThe reaction mixture was then warmed to 0° C.
2. stirringThe reaction mixture was stirred at room temperature for 30 min
3. stirringto stir 12 h at room temperature
4. customThe reaction was quenched with 1 N HCl
5. extractionextracted with ethylacetate (100×3)
6. dry with materialthe combined organic phases were dried over Na2SO4
7. filtrationfiltered
8. customevaporated under reduced pressure
9. customPurification by column chromatography

ORD-Eintrag

ord-c9870f247044481baceccdb03ed73db8

Quelldatensatz

uspto-grants-2013_03

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08394859B2